T71.164A (Asphyxiation due to hanging, undetermined, initial encounter) compared with T71.164S (Asphyxiation due to hanging, undetermined, sequela), from the official CMS tabular data. T71.164A and T71.164S code the same injury at a different phase of treatment.
Same underlying diagnosis, different encounter phase.
The 7th character records the phase of care for the encounter being coded, so a single encounter takes one of these characters, not several. Review whether both phases belong on the same episode of care.
Source: ICD-10-CM Official Guidelines, Section I.C.19.a
Same injury, other encounter phase. T71.164A and T71.164S code the same injury at a different phase of treatment, set by the 7th character.
The 7th character records the type of care given at the encounter being coded (ICD-10-CM Official Guidelines, Section I.C.19.a), so one encounter takes one of these, not both.
| T71.164AAsphyxiation due to hanging, undetermined, initial encounter | T71.164SAsphyxiation due to hanging, undetermined, sequela | |
|---|---|---|
| Billing status | Billable | Billable |
| Classification | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) | S00-T88 — Injury, Poisoning and Certain Other Consequences of External Causes (S00-T88) |
| Definition | Asphyxiation due to hanging, undetermined, initial encounter is a billable ICD-10-CM diagnosis code (T71.164A). | Asphyxiation due to hanging, undetermined, sequela is a billable ICD-10-CM diagnosis code (T71.164S). |
| 7th character | The appropriate 7th character is to be added to each code from category T71 | The appropriate 7th character is to be added to each code from category T71 |
| Use additional code | code for any associated injuries, such as: crushing injury of neck (S17.-) fracture of cervical vertebrae (S12.0-S12.2-) | code for any associated injuries, such as: crushing injury of neck (S17.-) fracture of cervical vertebrae (S12.0-S12.2-) |
Derived from the official CMS ICD-10-CM tabular data (FY2026). Not billing advice; verify sequencing rules for the encounter. All data sources